This invention is a shopping cart of the type frequently referred to as a supermarket cart which according to the invention is made of resin combined with and strengthened by U-shaped metal channel members.
Shopping carts used by customers in supermarkets, grocery stores and self-service merchandising stores to convey selected merchandise through the store to the cashiers, in their early stage of development were predominately made of metal, most frequently of steel metal tubing or rods. Such carts are still being made having a metal basket supported on a metal carriage on wheels, with the basket on a metal framework provided with a push handle at the rear of the carriage. Additionally an interiorally folded section is arranged for forward unfolding from the rear of the basket to provide a seat for a youngster or for convenient conveyance of small articles of merchandise. Such carts are usually constructed to be nestable by making their rear wall pivotable toward the basket interior about a pivot region under the handle. The basket portion of each cart can thus be pushed within the basket of an immediately forward cart to permit compact storage of a line of carts.
More recently carts of this type have been made with a basket substantially entirely of resin to reduce the damage experienced with metal from impact dents and rusting with age. To make carts entirely of resin requires use of considerable more material than earlier carts, causing such carts at times to be heavier and more bulky than metal shopping carts.
The invention herein presented is a resin basket of resin such as polypropylene combined with a metal support and a working backing framework of channels having a rectangular U-shaped cross-section in which the amount of resin required for the desired strength can be reduced considerably, resulting in a much lighter weight than when the cart components are made principally of all of resin or all metal. With less resin, the cost of production of such carts can also be reduced.
The metal channels providing the basket support framework, for sake of corrosion protection and appearance are coated with electrostactically applied powder resin heated to a temperature for an encasing flow coating of the metal members with resin. The channel shape provides a selective directional strength to portions of the carriage greater than is possible with tubular members, especially in the direction of forward movement of the cart. In addition, channel sections from the support framework are arranged to extend upwardly into the sides of the basket region with the U-shape facing the resin into which groves are molded for snug receipt of the leg portions of the channel members. This imparts a reinforcement to the resin sides while the resin of each side acts as a matrix for receipt of a channel extension thereby imparting a smooth face to the interior surface of the basket where the combination occurs.
In view of the foregoing a principal object of the invention is to provide a combined metal and resin shopping cart in which the amount of resin required for the carriage function can be minimized with a corresponding reduction in weight of the cart as well as cost of construction.
A feature of the invention lies in the fact that it can be made lighter in weight than carts made principally of resin or principally of metal, which permits greater ease of maneuverability and reduction in possible damage.
Other features of the present invention compared to tubular steel carts are quieter operation with no metal rattle sounds, longer appearance of newness because of lack of exposure of metal to rust and improved styling possible with plastic molding into rounded contours.
The present cart will less likely cause damage by bumping into parked vehicles or store fixtures or articles carried in the basket because there are no metal edges to harshly engage such items.
Besides being less in weight than steel tubular framed carts, the present cart is corrosion resistant and can be molded to reduce impact damage as well as molded in colors to match store colors and decor.
Compared to all plastic carts the present cart can be constructed with greater overall strength, less weight and bulkiness, less nesting space, and greater storage space under the basket.
The terms xe2x80x9cchannelxe2x80x9d and xe2x80x9cU-shapedxe2x80x9d channel or bar as used herein refer to a rectangular cross sectional longitudinal member having an elongated flat face side with a pair of relatively short legs extending right angularly away from the face at opposite edges of the member.
The channel is made of metal such as steel, aluminum, copper or any of a number of metal alloys. By way of example without intending to be limiting, the channel herein may be of steel approximately 1xc2xdxe2x80x3 wide, xe2x85x9xe2x80x3 thick with xe2x85x9cxe2x80x3 legs.
Still another feature of the invention is that by use of metal channels instead of metal tubes, a directional strength can be selectively designed into the basket support frame and into the sides of a cart where the reinforcement can provide the most advantage. In other words the U-shaped cross section of the channels can provide a greater strength directionally against bending in comparison to tubular members. Accordingly the support structure of the carriage and reenforcement of the basket sides can be imparted a strength in directions desired.
Other objects and features which are believed to be characteristic of my invention are set forth with particularity in the appended claims. My invention however, both in organization and manner of construction, together with further objects and features thereof, may be best understood with reference to the following description taken in connection with the accompanying drawings.